1. Field of the Invention
The present invention relates to a head assembly for use with a magnetic disk drive for a computer.
2. Description of the Related Art
In response to recent downsizing and density increasing of a magnetic disk drive, the flying height of a head slider has been reduced and it has been desired to realize contact recording/reproduction such that the slider flies at a microscopic height from a recording medium or comes to contact with the recording medium. In a conventional magnetic induction head, a decrease in peripheral speed (relative speed between the head and the recording medium) due to a decrease in diameter of a magnetic disk causes a deterioration in reproductive output. It has therefore been desired to develop a magnetoresistive head (MR head) or a giant magnetoresistive head (GMR head) which can obtain a large reproductive output even at a low peripheral speed with no peripheral speed dependence of reproductive output. It should be noted that the term of magnetoresistive head (MR head) used in this specification includes giant magnetoresistive head (GMR head).
In the MR head, a constant sense current is supplied to a magnetoresistive element (MR element) to convert changes in magnitude of a signal field leaking from a recording track of the recording medium into changes in resistance, thereby reproducing the information recorded on the medium as changes in voltage. The MR element of the MR head is formed generally by a thin-film process or the like. The MR head further has a coil for writing data to the recording medium. The head slider is mounted by adhesion or the like on a front end portion of a suspension formed of stainless steel.
Lead lines for connecting the MR element and the coil to a recording and reproducing circuit in a magnetic disk drive are formed by copper patterns printed on the suspension. By mounting the suspension on a front end portion of an actuator arm, the MR element and the coil are connected through a flexible printed circuit board (FPC) or the like to the recording and reproducing circuit.
In the suspension for supporting a conventional MR head slider, a pair of lead lines connected to the terminals of the MR element are electrically open, or the lead lines and a ground line connected to a magnetic shield for the MR element are electrically open. Accordingly, when a worker charged with static electricity handles such a suspension having the MR head slider or carries the suspension contained in a static-prone plastic case or the like, an excess current due to the static electricity flows into the MR element to burn the MR element, or the static electricity is discharged between the MR element and the magnetic shield to cause burning of the MR element.